Centralize amendment introduction date on one field, ditch offered_at and submitted_at fields (keep proposed_at field, optional for Senate amendments)
Centralize amendment introduction date on one field, ditch offered_at and submitted_at fields (keep proposed_at field, optional for Senate amendments)

unitedstates/congress,boblannon/congress,chriscondon/billtext,Nolawee/congress,Nolawee/congress,sunlightlabs/congress-opencongress,sunlightlabs/congress-opencongress,boblannon/congress,chriscondon/billtext,unitedstates/congress